ONE day last summer, Charlie Martin felt a sharp pain in his lower back. But he couldn’t jump into his car and rush to the doctor’s office or the emergency room: Mr. Martin, a crane operator, was working on an oil rig in the South China Sea off Malaysia.

He could, though, get in touch with a doctor thousands of miles away, via two-way video. Using an electronic stethoscope that a paramedic on the rig held in place, Dr. Oscar W. Boultinghouse, an emergency medicine physician in Houston, listened to Mr. Martin’s heart.

“The extreme pain strongly suggested a kidney stone,” Dr. Boultinghouse said later. A urinalysis on the rig confirmed the diagnosis, and Mr. Martin flew to his home in Mississippi for treatment.

Mr. Martin, 32, is now back at work on the same rig, the Courageous, leased by Shell Oil. He says he is grateful he could discuss his pain by video with the doctor. “It’s a lot better than trying to describe it on a phone,” Mr. Martin says.

COULD we cure diseases faster, or at least better control them, through crowd-sourcing?

That is the premise behind social networking sites like CureTogether.com and PatientsLikeMe.com, which offer online communities for patients and collect members’ health data for research purposes.

PatientsLikeMe provides forums where more than 65,000 members with epilepsy, multiple sclerosis and more than a dozen other disorders are encouraged to share details about their conditions and the success or pitfalls of specific drug treatments.